This proposal requests funds to enable young investigators to attend the 24th International Herpesvirus Workshop at the Massachusetts Institute of Technology in Cambridge, MA, July 17-22 1999. The International Herpesvirus Workshop is the premier scientific meeting for herpesvirus researchers, and the only meeting with an interdisciplinary focus on all the major subfamilies of herpesviruses and all aspects of research from molecular biology to clinical studies. The strength of the Workshop rests on the cross-fertilization that results from comparison of different herpesviruses, different approaches to key questions and on the support and participation of leading researchers in the field, most significantly including promising young investigators and students in training. Moreover, the forum is truly international, with broad-based world-wide attendance. The medical importance of this meeting is clearly indicated from the wide variety of diseases caused by the now recognized eight human herpesviruses. These include skin and eye ulcerations (HSV-1), genital lesions (HSV-2), recognized eight human herpesviruses. These include skin and eye ulcerations (HSV-1), genital lesions (HSV-2), meningitis and encephalitis (HSV-1 and HSV-2), infectious mononucleosis (EBV), chicken pox and shingle (VZV). CMV is a major cause of birth defects including mental retardation, blindness and deafness due to congenital transmission but also a significant opportunistic pathogen in AIDS patients and organ transplant recipients. More recently, CMV and HSV have been implicated as pathogenic contributors in the development of atherosclerosis. Cancer has also been associated with herpesvirus infections. EBV is associated with Burkitt's lymphoma, other B cell neoplasias and nasopharyngeal carcinoma. The most recent human herpesvirus discovered (HHV-8 or KSHV) is associated with Kaposi's sarcoma in AIDS patients and other immunosupressed persons and in other groups. All of the herpesviruses persist for life and therefore pose significant problems in the treatment of immunologically compromised persons. Disease due to reactivation of most human herpesviruses are a significant cause of morbidity and mortality in various immune patient populations. Shingles and post-herpetic neuralgia are problems in the elderly. Animal herpes significant economic importance to the poultry (Marek's and others), swine (pseudorabies virus), cattle (several bovine herpesviruses) and horses (several equine herpesviruses. In addition, these animal herpes serve as important model systems for studying herpesvirus pathogenesis. Finally, recombinant DNA technology permits the design of novel vaccines for controlling the spread of animal herpesvirus infection and the design of herpesvirus vectors for gene therapy. Workshop sessions will take an interdisciplinary approach to the following topics: virus structure, mechanism of virus entry and cell- cell spread, membrane proteins, pathogenesis and latency, DNA replication, vaccination and the immune response, transcriptional control, regulation of gene expression, chemotherapeutic targets, and virus gene therapy.